Apparatus and method for modification of flow of air, gases, and the like



H. A. REEcE 2,269,477

APPARATUS AND METHOD FOR MODIFICATION OF. FLOW OF AIR, GASES, AND THELIKE Jan. 13, 1942.

Filed July 16, 1940 2 Sheets-Sheet l ATTORNEY.

INVENTOR. EMA.REEZ.

llll 2 Jan. 13, 1942. H. A. REECE APPARATUS AND METHOD FOR MODIFICATIONOF FLOW AIR, GASES, AND THE LIKE 2 Sheets-Sheet 2 -Filed July 16, 1940INVENTOR. 7 MEBTA.EEEE M 2 ATTORNEY.

Patented Jan. 13, 1942 APPARATUS AND METHOD FOR MODIFIOA- TION OF FLOWOF AIR, GASES, AND THE Herbert A. Reece, Clevela signor to MeehaniteMetal Corporation, a cor;-

poration of Tennessee Application July 16, 1940, Serial No. 345,719

(Cl. 26ii-30) 20 Claims.

My invention relates to supply apparatus for delivery of air and thelike, such as wind boxes for metallurgical and other furnaces, andto'the operation of the same.

My present invention, herein described. is -re lated in subject matterto my invention described in my United States Letters Patent No.2,197,947 issued on-April 23, 1940, and to my invention described in myco-pending United States patent application, Serial No. 330,878, filedApril 22,

1940, and is directed to the same and similar problems of furnaceoperationand control of air flow as is set forth in said issued patentand said co-pending application.-

In the following discussion and description the operation and structureof a cupola for the remelting of metal will be referred to, but it is tobe understood that my invention includes the 7 structure and operationof all furnaces or similar devices wherein a blast of air or other gase.is supplied through a plurality of tuyeres or like openings to theinterior of the furnace or similar device.

It is an object of my invention to provide a wind box for supplying anair blast at substantially equal velocities to. each of a plurality oftuyeres.

A further object is the provision of improved apparatus and method forsupplying an air blast to each of several tuyere at desired velocitieswithout disturbing the relative volume of air supplied to each of theseveral tuyeres.

Another object is the control of the air blast delivered to a'pluralityof tuyeres of a furnace from a wind box.

Another object is the modification of the current of air blast movingthrough a wind' box.

Another object is the modification of the direction of portions of anairblast passing through a wind box from an inlet to a plurality ofoutlets.

Another object is the provision of apparatus and method of modifying aflow of air and like gases through a common distributing chamber.

Another object is the provision of improved apparatus and method foreliminating of .tangential ilow of air through a wind box.

Another object is the provision for utilizing the force of tangentialflow of air moving through the wind .box to provide a yieldableresistance to the flow of air moving through the wind box toward thetuyere entrances.

Another object is the provision for balancing tangential flow of airwith longitudinal iiow of air to equalize said flow of air supplied to aplurality of tuyres from a wind box.

nd Heights, Ohio, as-

Another object i the-provision for equalizing the flow of air through acommon distributing chamber by resisting members movable by the flow ofair.

Another object is the provision for counter-balancing a resistance toair flow with a yielding to the air flow in a manner to equalize thevelocity of the air flow in diflerent localities of the wind box to.supply the air to the outlets of th wind box at uniform velocity.

Other objects and a fullerunderstanding of my invention may be had byreferring to the following description and claims, taken in conjunctionwith the accompanying drawings, in which:

Figure 1 is an elevational view of. a wind box mounted upon a cupolaj 7Figure 2 is a cross-sectionaiview taken lengthwise of the cupola andwind box shown in Figurel; i y

Figure 3 is a transverse cross-sectional view taken through the. line3-3 of Figure 2;

Figure 4 is an enlarged detailed view of a revolvable vane membermounted within t e wind box as shown in Figures 2 and 3; p i t Figure 5is an endwiseview of the revolvable vane member shown in Figure 4'asviewedin the direction of the arrows 5 5 of Figure 4;

Figure 6 illustrates a modified form oi revolvable vane member in whichthe vanes are spirally and disposed;

, Figure 7 is an endwise view of the vane members shown in Figure 6 asviewing the vane member in the direction of the arrows 1-1 of Figure 6;l

Figure 8 isa view of amodified form of apparatus in which the severalvane members are not. connected together to operate in unison;

Figure 9 is a view largely 'diagrammatical in nature to illustrate thecooperative relationship of the parts of the apparatus and is a view ofthe wind box laid out in the flat upon opening ofthe wind box along alongitudinal seam, the figure showing theview as seenfrom the. inside ofthe furnace.

Inasmuch as the invention disclosed herein is directed to the wind boxand the portion of the cupola adjacent thereto it has not beenconsidered necessary to show all parts of thecupola and therefore thedrawings do not include the top portion and the bottom portion of thecupola, which portions may be considered as having the usual form. Also,for purposes of simplicity in illustration, the usual tap hole and slaghole are not shown. It has also been considered unnecessary toillustrate such other openings as a cleanout door, breast arch, ordrop-bottom doors. The cupola with which the invention is associatedandwhich is described herein may be considered, however, as having all ofthe part necessary for the usual operation of the same.

As shown in the several views of the drawings the cupola body or shell2! is in the form of a cylindrical shaft, the inner walls of the cupolabody 2! being lined by the fire brick lining 24. The body 2| and thelining 24 are mounted upon the usual bottom plate and thereby formingthe enclosed shaft of the cupola.

A wind box 22 of cylindrical shape is mounted upon the cupola body 2i bywelding or other suitable means and in the embodiment shown, the outerwall of the cupola body forms one of the enclosing walls of the wind box22. It is is therefore seen from the views of the drawings that the windbox 22 forms an enclosed jacket surrounding the cupola body 2| in such away that air introduced into the wind box may circulate entirely aroundthe cupola body.

The inlet conduit 22 is in communication with the air blower or othersource of an air blast (not shown) and the inlet conduit 23 is connectedto the wind box 22 at the upper portion of the wind box 22 so as toafford communication between the air blower and the inlet opening 25 ofthe wind box 22.

In the cupola illustrated there are six tuyeres extending through thewall and lining of the cupola body 2| to establish communication betweenthe interior of the shaft of the cupola and the wind box 22. Tuyeres 20,SI and 22 as seen from the inside of the shaft of the cupola areillustrated in Figure 2. All six tuyeres, 30, 3|, 32, 33, 34 and 25 areshown in dotted lines in Figure 3 and are also illustrated in Figure 9.These tuyeres are of substantially equal size and areuniformly spacedaround the periphery of the cupola. It is to be noted that the tuyeresenter the cupola body at a low level in the cupola and communicate withthe wind box in a lower portion thereof. In order that the operator maylook into the tuyeres from the outside of the furnace, peep holes areprovided in the wind box opposite each of the tuyeres and mica or othersuitable substance is sealed over these keepholes. Except whennecessary, keep hole covers 28 hingedly connected to the wind box 22 arekept in position over the keep holes by means of the latch members 29. V

The arrangement of the wind box, the inlet and the outlets to thetuyeres is such that without my control apparatus the blast of airentering the wind box 22 from the inlet 25 circles around the interiorof the wind box in substantially one circumferential direction, the airso moving in currents of unequal velocity. The air blast thus movingthrough the wind box would be supplied to the tuyeres at unequalvelocities in the absence of adequate control of the flow of air. Theair circulating around the wind box tends to flow tangentially of theentrancesvof the tuyeres and for this reasoon this circular flow of airis generally referred to in the art as a "tangential flow. Withoutadequate control of such tangential" flow of air and of the velocity ofthe currents of air it is found that the air is supplied to the tuyeresat unequal velocities resulting in improper furnace operation. By thecontrol of the flow of air through the wind box in the manner heredescribed the velocity of the air is modified to provide a supply of airto the plurality of tuyeres at substantially equal velocity, thecirculatory and tangential flow of air being transformed into a verticalflow of uniform density and equal velocity to the tuyere entrances.

with reference to the views of the drawings there is shown positionedwithin the wind box below, and at a distance from, the inlet opening 25a plurality of vane members comprising vanes 2t radiating outwardly fromthe plurality ,of shafts 81. The shafts 21 are journalled to the wallsof the wind box 22 by being rotatively mounted within openings 29 andll) formed in the walls of the wind box. The vanes 38 radiatingoutwardly. from the shafts 31 are evenly spaced from each other as isshown in Figure 5. As the interior of the wind box is annular in shapeit is preferable to have the vane members constructed with the diameterat one end larger than the diameter at the other end, the larger end ofthe vane member being positioned adjacent the outer wall of the wind boxand the smaller end of the vane member being positioned adjacent theinner wall of the wind box. By the use of such wedge-shaped vane membersin the cross-sectional area of the wind box at the plane of the axialshafts 21 is substantially filled with the vane members, leaving only aminimum of open space not blocked by the vane members. Also, by havingthe larger diameter end of the vane members somewhat curved tocomplement the inner wall of the wind box 22, as better shown in Figure4, the interior cross-sectional area of the wind box is more effectivelyfilled or blocked. As is shown in Figure 3 the plurality of vane membersmade up of the vanes 22 extending from the axial shaft 31 substantiallyfills the cross-sectional area of the wind box and thus substantiallyforms a movable obstruction dividing the upper portion of the wind boxfrom the lower portion of the wind box.

The shafts 31 which form the axes for the vanes 2C extend radially outfrom the furnace and are disposed in one plane transversely of the windbox. Air moving through the wind box from the inlet 25 to the pluralityof tuyere entrances encounters the vane members. The

' vanes 22 are extended in a gradual curve or are cupped as theyradiate-from the shafts 21. By this form of the vanes the force of theair blast upon the upper half of the several vane members tends torevolve the vane members in one direction. As is more apparent in theend view of a vane member shown in Figure 5, the air blast tends tocatch" in the upwardly curved vanes on the right side of Figure 5 andthus tending to cause the vane member shown in Figure 5 to revolve in aclockwise direction.

Non-rotatively secured to the outer end of each shaft 21 extendedoutwardly of the wind box 22 is a gear ll. As the radiating vanes 28 arerigidly secured to the shaft 31 the revolution of the vanes 28 causesthe simultaneous rotation of the gears II. A large ring gear 42completely encircling the wind box 22 has gear teeth formed in its loweredge which enmesh with the teeth of the gears 4i. Therefore, rotation ofthe gears 4! causes the revolution of the ring gear 42 around the windbox, the gears II and the ring 42 being thereby synchronized to move inunison The upper edge of the ring gear 42 has ratchet teeth 43 formedthereon and one or more pawls 44 pivotally secured to the wall of thewind box engage the ratchet teeth 43 in such manner as to permit thering gear 42 to revolve in one direction and to prevent it to revolve inthe opposite direction. The spring 45 connecting the pawl 44 with thewall of the wind box urges the pawl 44 into engagement with the ratchetteeth 43 and also provides a retarding action to the revolution of thering gear 42 and hence the rotation of the gears 4|. The friction of theparts and the yield.- able resistance of the spring 45 providesaretarding action or drag upon the rotation of the shafts 31 and therevolution of the vanes 38 thereon. v

To prevent the locking or jamming of the ring gear 42 and the gears 4|there is provided an annular bearing support 48 which is secured bywelding or other suitable means to the outer wall counter-clockwise"direction and thus tend to reof the wind box. Rollers 41 rotativelymounted I onpins 46 extending inwardly from, the ring gear 42 roll uponand are supported by the bearing support 48. In this manner the weightof the ring gear 42 is borne by the annular support 48 rather'than uponthe gears 4|. The ring gear.

42 circles around and around the wind box upon the track formed by thesupport 48 upon the sist the downward flow of the air blast. It istherefore seen that the tangential force tends to urge the vane membersagainst revolving in the direction they otherwise would be permitted torevolve and thus somewhat counter-balances the downward force of the airblast'causing the vane members to revolve. The force of the air blastbrought into the upper portion of the wind box, however, causes the-vanemembers to yield to the force thereof, to revolve in the directionpermitted and to permit the air to thus pass downwardly from the upperportion of the wind box to the lower portion of the wind box. By thisarrangement the force of the tangential flow tends to yieldably urge thevane members against rotation while the dominant pressure of thedownwardly movingair blast overcomesthe yieldable resistance of the vanemembersto permit the air to flow downwardly at modified velocity.

This yieldable resistance offered by the force of the tangential flow isinaddition to the yieldable resistance which would otherwise. be offeredby therevolvable vane members by reason of friction of the parts, thespring pressed pawl, and

the inherent resistance to the flow of air offered by the shape anddisposition of the vane members.

By means of the yieldable resistance of the vanes'38 to the fiowof airthe velocity of the air flow through the wind'box is modified and isbrought into equilibrium in all locations through- V out thecross-sectional area of the wind box. As

trated by the diagrammatical view of Figure 9.

As indicated by the upper arrows the air blast entering the wind boxfrom the inlet 25 moves from the left to the right. This same directionof flow of the air blast would beconsidered as a flow in a clockwisedirection in the cross-sectional view of Figure 3. As has beenexplained, it is desirable to break up or diffuse this circulatory ortangential flow of air comprising eurrentsofunequalvelocity. If the vanemembers were positioned to revolve in the same general direction as thedirection of the tangential flow some of the force of the tangentialflow would tend to carry over into the lower portion of the wind box.However, by having the vane members revolve in such a direction as tooppose the undesired tangential" flow the movement of the air from theupper portion of the windbox to the lower portion of the wind box'willbe made independently of the force of this tangential flow. In Figure 9as the tangential flow is indicated as moving from left toright, therevolution of the vane members is in a counterclockwise direction asindicated by the curved arrows.

The curving disposition ofthe vanes 38 comprising each vane member istherefore such that downward movement of the air blast tends to rotatethe vane members in a single-clockwise direction. Also, by means of thering gear 42 moving in only one direction (by means of the ratchet teeth43 and pawl 44) the vane members are permitted to revolve in only onedirection, which in the view of Figure 9 would be in a counter-clockwisedirection. Therefore, not only by the shape of the vanes 38 but also bythe positive limitation means afforded by the ratchet and pawl on thering gear, are the vane members prevented from revolving in the samegeneral direction as the tangential" flow of air in the upper portion ofthe wind box.

Insofar as the flow of air in the upper portion of the wind box istangential, it will tend to prevent the vane members from revolving insaid the vane members are substantially. evenly distributed around thewind box and are vof'substantially the same size and subjectto the sameretarding action, there is a modification. of the air flow insubstantially the same way by all of the vane members. In addition, theconnecting means, provided by the ring gear tying in together all of therevolving vane members assist in the distribution of the airflow tosubstantially equalize the velocity of all portions of the air flowpassing from the upper portion of the wind box to the lower portion ofthe wind box. The described apparatus so modifies the velocity of theair flow and corrects the undesired tangential flow thatthe air issupplied to the plurality of tuyre openings in the lower portion of thewind box at substantially equal velocity.

' InFigures 6 and 7 there is illustrated a modifled form of vane memberin which the vanes are spirally disposed'relative to the shafts 3! aboutwhich they revolve. The disposition of the spirally disposed vanes 50 issuch that the vanes meet the force of the air blast at a compound angle;The general operation of the vane members having the spiral vanes 50 issimilar in principle to that of the vane members having the straightsided vanes 38, the vane members with the spiral vanes taking on some ofthe characteristics of a turbine.

In Figure 8 there is a modifiedform of ar- I rangement illustratedwherein each vane member is independent of the operation of the othervane members, the use of the ring gear 42 connecting the vane membersbeing eliminated. A ratchet wheel 52non-rotatively secured to the outerend the upper portion of the wind box to the lower 7 portion of the windbox. As the modifying force of each vane member would be approximatelythe same, the velocity of the air blast .would tend to equalize.Although there is a desirable modification of the velocity of the airblast and a correction of the tangential flow it is preferable to havethe vane members operatively connected together such as in the mannershown in Figures 1, 2 and 3 as giving more efficient results inequalization of the velocity of the air blast delivered to the tuvereentrances.

The results obtainable by the use of the apparatus and method of aircontrol herein described greatly increases the efficiency in theoperation of furnaces. The description and disclosure herein made willat once suggest other forms and arrangements in the carrying out of thedescribed invention but such other forms, arrangements and adaptationsare included within the teaching of the discovery and invention hereindisclosed by the drawings and description.

Although I have described my invention with a certain degree ofparticularity, it is understood that the present disclosure has beenmade only by way of example and that numerous changes in the details ofconstruction and the combination and arrangement of parts may beresorted to without departing from the spirit and the scope of theinvention as hereinafter claimed.

I claim as my invention:

1. In a furnace having a wind box for supplying a blast of air to alurality of tuyeres, said wind box having an inlet adapted tocommunicate with a source of an air blast and having outlets incommunication with said tuyeres, a plurality of revolvabie vane memberspositioned in said wind box intermediate of, and at a distance from,said inlet and said outlets and in the path of the air blast passingthrough the wind box, said vane members having radially extending vanesrevoluble on substantially horizontally disposed axes, said vane membersresisting said air blast and yielding thereto to revolve on said axes,respectively, the air blast revolving said vane members being modifiedin velocity to be supplied to said outlets at said modified velocity.

2. In a furnace having a wind box for supplying a blast of air to aplurality of tuyeres, said wind box having an inlet adapted tocommunicate with a source of an air blast and having outlets incommunicationwith said tuyeres, a plurality of revolvable vane memberspositioned around said wind box in the path of the said air blastpassing through the wind box from the inlet to said outlets to dividethe wind box into a portion adjacent the said inlet and another portionad- Jacent the said outlets, said vane members having axes disposedradially of said furnace and being revolvable by the force of said airblast,,the vane members providing a resistance to said air blastyieldable upon revolution of the vane members to modify the velocity ofthe air blast passing to said another portion of the wind box adjacentsaid outlets.

3. In a furnace having a wind box for supplying a blast of air to aplurality of tuyres, said aaeasvr wind box having an inlet adapted tocommunicate with a source of an. air blast and having outlets incommunication with said tuyeres, a plurality of revolvable vane memberspositioned in said wind box intermediate a portion of the wind boxadjacent said inlet and another portion of the wind box adjacent saidoutlets, the axes of the revolvable vane members being disposedsubstantially radially of the furnace and being distributedsubstantially uniformly around the wind box, said revolvable vanemembers providing a resistance to said air blast and revolving under theforce of the air blast to modify the velocity thereof, the air blastrevolving said vane members and to said another portion of the wind boxbeing supplied to said outlets at said modified velocity.

4. In a furnace having a wind box for supplying a blast of air to theentrances of a plurality of tuyeres communicationg with said furnace,said wind box having an inletadapted to communicate with a source of anair blast, a plurality of vane members positioned in said wind box tosubstantially separate the wind box into a portion adjacent said inletand another portion adjacent said entrances, said vane members havingaxes Journalled to said wind box and disposed substantially radially ofthe furnace, the vane members having vanes extending radially from saidaxes, said vanes recurrently meeting and resisting said air blast andyielding thereto to revolve on said axes, the recurrent resistance andyieldance by the revoluble vanes modifying the velocity of said airblast supplied to said entrances from said another portion of the windbox.

5. In a furnace having a wind box positioned around the body of thefurnace for supplying a blast of air to the entrances of a plurality oftuyeres communicating with said furnace, said wind box having an inletadapted to communicate with a source of an air blast, .an obstructionmounted within the wind box to divide the wind box into a portionadjacent said inlet and a portion adjacent said outlets, saidobstruction comprising a plurality of vanes radiating from a pluralityof axes disposed radially of said furnace and distributed around saidwind box, said vanes being revoluble about said axes recurrently toresist, and to yield to, said air blast. the air blast meeting andrevolving said vanes being modified to be supplied at substantiallyequal velocities to said tuyere entrances.

8. In a furnace having a wind box for supplying ablastof air to aplurality of tuyeres, said wind box having an inletadapted tocommunicate witha source of an air blast and having outlets incommunication with said tuyeres, a plurality of vane members positionedin said wind box intermediate of, and at a distance from, said inlet andsaid outlets'dividlng the wind box into ad- Jacent portions, said vanemembers having axes journalled on said wind box and disposed radially ofthe furnace at intervals around the wind box, said vane members havingvanes extended from said axes and disposed recurrently to meet, and tobe revolved about said axes by, said air blast passing through the windbox, said vanes successively yieldably resisting said air blast inrevolving about said axes, the yieldable resistance of said vanesmodifying the velocity of said air blast delivered to said outlets.

7. In a furnace having a wind box for supplying a blast of air to aplurality of tuyres, said wind box having an inlet adapted tocommunicate with a source of an air blast and having outlets incommunication with said tuyeres, a plurality of movable resistorspositioned in said wind box intermediate of, and at a distance from,said inlet and said outlets and in the path of the air blast passingthrough the wind box, said movable resistors being revoluble about axesdisposed radially of said furnace at intervals around said wind box,said'movable resistors extending substantially throughout thecross-sectional area of the wind box substantially to separate theportion of the wind box adjacent the inlet and the portion of the windbox adjacent the outlets, the revolution of said movable resistors bythe force of said air blast recurrently moving said resistors into thepath of said air blast to yieldably resist the same, the recurrentresistance providedby said resistors modifying the velocity of. the airblast supplied to said outlets from the wind box.,

the wind box into a portion adjacentthe inlet and a portion adjacent theoutlets, the vane members being revoluble by said-air blast on axesdisposed substantiallyradially of 'the furnace and distributed aroundthe'wind box, and means. for limiting the revolutionsof said vanemembers to revolvement in a 'direction opposed to said circumferentialdirection of the'airblast, said vane members providing a yieldableresistance to the air blast moving from the portion of the wind 8. In afurnace having a wind box for supplying a blast of air to a plurality oftuyeres entering the furnace, said wind box having an inlet adapted tocommunicate with a source of an air blast and having outlets incommunication with said tuyeres, an obstruction positioned in said windbox intermediate the inlet'and the outlets for resisting the flow of airthrough the wind I box toward the outlets, said obstruction including aplurality of movable members arranged in groups radiating from aplurality of axes disposed trans- .versely of said wind box, saidmovable members being adapted to revolve about said axes and torecurrently pass through the plane of said plurality of axes, the saidmovable membersin said plane resisting saidair blast and revolving to aposition away from said plane in yieldance to the force of said airblast, the revolvement of said movable members providing for therecurrent yieldable resistance of said movable members to the air blastto provide for the modification of the velocity of the air blastsupplied to said outlets.

9. In a furnace having a wind box positioned around the body of thefurnace for supplying air to a plurality of tuyeres entering thefurnace, said wind box having an inlet adapted to communicate with asource of an air blast and having outlets in communication with saidtuyres, the ar- .rangement of the wind box, inlet and outlets being suchthat currents of air of unequal velocities circulate and move throughthe wind box, an

box adjacent the inlet to the portion of the wind box adjacent theoutlets to modify the direction and velocity of the air blastsupplied tosaid outlets. 11. In a furnace having a wind' box positioned around thebody of the furnace for supplying air to a plurality of tuyres enteringthe furnace, said wind box having an inlet adapted to communicate with asource of an air blast and having outlets in communication with saidtuyeres, the

" arrangement of the wind box, inlet and outlets being such that theblast of air entering the wind box from the inlet circles around withinthe wind box in one circumferential direction, the combination of aplurality of vane members positioned in said wind box intermediate of,and lat a distance'from, said inlet and said outlets to. divide the windbox into a portion adjacent the inlet and a portion adjacent theoutlets,the vane members being revoluble by said 'air blast on axes disposedsubstantially radially of the furjnace and distributed around thewindbox, re-v tarding means for retarding, the revolutions of said vanemembers in resistance to said'a'ir blast, and meansfor limiting therevolutions of said vane members torevolvement in a direction opposed tosaid circumferential direction of the air blast, said vane membersproviding a yieldable resistance to the air blast moving from theportion of the wind box adjacent theinlet to the obstruction positionedin said wind box to divide the wind box into a portion adjacent theinlet and a portion adjacent the outlets, said obstruction comprising aplurality of vanes arranged in groups radiating from axes disposedradially of, and distributed around, said furnace, said vanes resistingsaid currents of air circulating around the wind box to modify thevelocity thereof, the air moving through the wind box from the inlet tothe outlets revolving said vanes about said axes into positionrecurrently to meet and resist said currents of air, the revolution ofsaid vanes providing for the successive disposition of said vanes in theplane of the said obstruction and the successive yielding of the vanesto the force ofthe air blast to modify the velocity of the air blastsupplied to said outlets.

10. In a furnace having a wind box positioned around the body of thefurnace for supplying air to a plurality of tuyeres entering thefurnace, said wind box having aninlet adapted to communicate with asource of an air blast and having portion of the wind box adjacent theoutlets to modify the direction and velocity, of the air blast suppliedto said outlets.

12 In a furnace having a wind box positioned around the body ofthefurnacefor supplying air to a plurality of tuyeresentering the furnace,said wind box having aninlet adapted to communicate, with a source of.an air blast and'having outlets in communication with said -tuyeres,the arrangement of the wind box, inlet and out lets being such thatthe,blast of air entering the wind box from theinlet circles around withinthe wind box in one circumferential direction, the

g combination-of a plurality of vane:members positioned in said windboxintermediate of, and at a distance from, said inlet and said outlets todivide the wind box into a portion adjacent the inlet and a portionadjacent the outlets, the vane members being revoluble by said air blaston axes disposed substantially radially of thefurnace and distributedaround-the wind box, retarding means for retarding the revolutions ofsaid vane members in resistance to said air blast, connecting meansoperatively connecting said vane members to synchronize the revolutionsthereof in unison, and means for limiting the revolutions of saidtuyerescommunicating with said furnace, said wind box having an inletadapted to communicafe witha source of an air blast, air blast resistingmeans positioned in said wind box to divide the wind box into a portionadjacent said inlet and a portion adjacent said entrances. saidresisting means including a plurality of vanes extending intermediatethe walls of said wind box,

said vanes being arranged in groups radiating from'a plurality. of axesextended in a plane disposed transversely of said wind box, said vanesbeing revoluble by said air blast on said axes to recurrentlymove in andout of said plane, the

, vanes'in .said plane yieldably resisting said air blast to modify thevelocity thereof, the air blast being supplied to said tuyre entrancesat said modified velocity.

, 14. In a furnace having a wind box positioned around the body of thefurnace for supplying air to a plurality of tuyeres entering thefurnace, said wind boxhaving an inlet adapted to communicate with asource of an air blast and having outlet in communication with saidtuyeres,

the arrangement of the wind box, inlet and out-,

lets being such that currents of air entering the wind box circulatearound in one general circumferential direction, a plurality ofrevolvable vane members positioned in said wind box in a planeintermediate of, and at a distance from, the said inlet and saidoutlets, said vane members beingrevolvable by the force of said-airblast to recurrently swing in and out of said plane, retarding meansforretarding the revolution of the vane members, and means for limiting therevolution of said vanemembers to one direction, said vane membersrevolving to oppose said currents of air circulating in onecircumferential direction and to yieldably'resist the air blast passingthrough the wind box from the inlet to the outlets, said air blastsupplied to said outlets being modified in direction and velocity bysaid vane members.

15 In a furnace having a wind box positioned around the bodyof thefurnace for supplying air to a plurality of tuyres entering the furnace,said wind box having an inlet adapted to communicate with a source of anair blast and having outlets in communication with said tuyeres.

the arrangement of the wind box, inlet and outlets being such thatcurrents of air entering the wind box-circulate around in one generalcircumferential direction, a plurality of vane members positioned insaid wind box intermediate of said inlet and said outlets, said vanemembers being revolvable on a plurality of axes disposed in a planepassing transversely of said wind box intermediate of, and at a'distancefrom said inlet and said outlets, connecting means operativelyconnecting said vane members to synchronize the revolving thereof inunison, and ratchet means limiting the, revolvement of the vane membersto one rotative direction, said vane members being revolvable inopposition to said currents of air circulating around the wind box andin yieldable resistance to the air blas pas ing through the wind box tosaid outlets, the air blast being modified by said vane members to besupplied to said outlets at substantially equal velocity.

16. In a furnace having a wind box for supply. ing a blast of air to aplurality of tuyeres, said wind box having an inlet adapted tocommunicate with a source of anair blast and having out. lets incommunication with said tuyeres, the arrangement of the wind box, inletand outlets being such that the air blast entering the wind box from theinlet flows tangentially of the furnace. a plurality of vanes positionedin said wind box intermediate of, and at a, distance from, said inletand said outlets and in the path of the air blast passing through thewind box, said vanes being arranged in groups radiating from a pluralityof axes and being revoluble around said axes, said vanes being disposedto be urged to revolve in one direction by said tangential flow and tobe urged to revolve in the opposite direction by the force of the airblast moving longitudinally of the wind box toward said outlets, saidvanes being revolvable in only said opposite direction, the urging ofthe vanes in said one direction providing a yieldable resistance to therevolution in said oppolsite direction, said vanes providing a yieldableresistance to said blast of air moving toward the outlets to modify thevelocity of the air blast supplied to said outlets.

17. In a furnace having a, wind box for supplying a blast of air to aplurality of tuyeres, said wind box having an inlet adapted tocommunicate with a source of an air blast and having outlets incommunication with said tuyeres, the arrangement of the wind box, inletand outlets being such that the air blast entering the wind box from theinlet flows tangentially of the furnace, a plurality of vanes positionedin said wind box intermediate of, and at a distance from, said inlet andsaid outlets and in the path of the air blast passing through the windbox, said vanes being arranged to revolve about axes disposedsubstantially parallel to a plane passing through said outlets and aplane passing through said inlet, the vanes in revolving on said axesrecurrently extending into the path of said tangential flow vof air toresist the same, the said vanes being concavely formed to revolve, underthe force of the air blast moving longitudinally of the wind box andtoward the plane of the outlets, in a direction opposing the saidtangential flow, said vanes yieldably urged in one direction by thetangential flow and yieldably revolving by the force of saidlongitudinal flow of air modifying the flow of air supplied to saidoutlets.

18. In a furnace having a wind box for supplying a blast of air to aplurality of tuyres, said wind box having an inlet adapted tocommunicate with a source of an air blast and having outlets incommunication with said tuyeres, the arrangement of the wind box, inletand outlets being such that the air blast entering the wind box from theinlet flows tangentially of the furnace, a plurality of vanes positionedin said wind box intermediate of, and at a distance from, said inlet andsaid outlets and in the path of the air blast passing through the windbox, the said vanes being mounted to recurrently resist said tangentialflow of air and to recurrently yield to the flow of air movinglongitudinally of the wind box toward the outlets to move in oppositionto the force of said tangential flow, the yieldable movement of saidvanes in opposition to said resistance modifying the velocity of the airblast 20. In the operation of a furnace, the method of furnishing an airblast to a plurality of tuyeres' moving through the wind box, andconnecting means operatively connecting said vanes to move in unison,the modification of the velocity of the air blast by said plurality ofvanes providing for the supply of air to said plurality of outlets atsubstantially equal velocities,

19. The method of controlling the flow of air supplied to a plurality oftuyeres of a furnace, comprising: passing an air blast through aconduit, supplying the air blast through the conduit into an enlargedair chamber, resisting the tangential flow of air set up in said airchamber,

resisting the flow of the air blast moving longitudinally of the airchamber at an angle to said tangential fiow and from one portion 01' theair chamber to another,'yielding said latter resistance in opposition tosaid first resistance, passing said air blast through said yieldingresistance into said another portion oi'the air chamber, and supplyingthe air blast from said another portion of the wind box to said tuyresat velocities modified by said yieldable resistance.

having predetermined volume capacities from a wind box whereintangential flow of air currents are encountered, comprising: resistingsaid tangential fiow of air in a first portion of the wind box,resisting the fiow of air moving longitudinally of the wind box at anangle to said tangential flow and from said first portion of the windbox to a second portion of the wind box, yielding said latter resistanceto permit the flow 01 air to said second portion of the wind box,opposing said yielding with the resistance to said tangential fiowto'provide a yieldable resistance to the flow of air from said firstportion of the wind box to a second portion of the wind box inaccordance with the force of said tangential flow, and supplying the airfiow modified by said yieldable resistance to the plurality of tuyeresat substantially equal velocities.

HERBERT A. REECE.

